The present invention relates generally to fans and more specifically to electrically operated ceiling fans of the type normally used in homes or businesses to create a circulation of air within a room or other confined space.
Ceiling fans have been known for a long period of time. Such fans typically are used during the summer months to move air from the ceiling toward the floor of a space to enhance air conditioning systems thereby requiring less cooling of the ambient air in order to maintain comfort. Such fans may be operated in a reverse direction to move air from the floor toward the ceiling. Such operational format is normally utilized during the winter months to move heated air away from the ceiling and back toward the floor of an enclosed space to thereby create a situation where less heat is required to maintain the particular space comfortable for the occupants.
Throughout the remainder of this Application, the terms "trailing edge" and "leading edge" may be utilized from time to time when describing certain features of the ceiling fan constructed in accordance with the principles of the present invention. When so utilized, those terms will be used with respect to the rotation of the fan as it is normally used in the summer months to move air from the ceiling toward the floor as it rotates. That is, air is moving downwardly directly beneath the fan blades as they rotate.
Prior art fans known to Applicant typically are constructed utilizing blade irons which are affixed at the inner periphery thereof to a rotor which is turned by a motor when it is electrically energized. The blade irons include an arm extending outwardly to which the blade of the fan is affixed. Typically the entire fan blade is exposed to view when viewed from below. Typically such prior art fan blades are narrow at the blade root and converge outwardly so that the blade tip is wider than the blade root.
Recent ceiling fans have been constructed in such a way that the rotor is completely enclosed and the roots of the fan blades appear to extend through such enclosure. This tends to provide an appearance of an integrated swept wing design to the fan. Such design provides a more streamlined appearance, including an appearance where the taper of the fan blade is reversed from that normally encountered in that the root is wider than the tip. This new design presents complex shapes and configurations which are expensive to manufacture and wherein maintenance is difficult and therefore costly, particularly where the fan blade must be removed.
It is therefore desirable to provide a ceiling fan which produces the swept wing design but which is relatively simple to manufacture and assemble and to also provide the ability to convert currently existing fans to such new swept wing design.